Guarantee 8 bytes of alignment in Thread::into_raw #143859
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r? libs-api, this adds an alignment guarantee to the unstable |
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ping @rust-lang/libs-api, as this provides a new guarantee, arguably needing FCP (and at a minimum team involvement) |
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@rfcbot fcp merge |
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Team member @dtolnay has proposed to merge this. The next step is review by the rest of the tagged team members: No concerns currently listed. Once a majority of reviewers approve (and at most 2 approvals are outstanding), this will enter its final comment period. If you spot a major issue that hasn't been raised at any point in this process, please speak up! See this document for info about what commands tagged team members can give me. |
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🔔 This is now entering its final comment period, as per the review above. 🔔 |
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The final comment period, with a disposition to merge, as per the review above, is now complete. As the automated representative of the governance process, I would like to thank the author for their work and everyone else who contributed. This will be merged soon. |
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@bors r+ rollup |
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Guarantee 8 bytes of alignment in Thread::into_raw When using `AtomicPtr` for synchronization it's incredibly useful when you've got a couple bits you can stuff metadata in. By guaranteeing that `Thread`'s `Inner` struct is aligned to 8 bytes everyone can use the bottom 3 bits to signal other things, such as a critical section, etc. This guarantee is thus very useful and costs us nothing.
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Guarantee 8 bytes of alignment in Thread::into_raw When using `AtomicPtr` for synchronization it's incredibly useful when you've got a couple bits you can stuff metadata in. By guaranteeing that `Thread`'s `Inner` struct is aligned to 8 bytes everyone can use the bottom 3 bits to signal other things, such as a critical section, etc. This guarantee is thus very useful and costs us nothing.
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Rollup of 9 pull requests Successful merges: - #140871 (Don't lint against named labels in `naked_asm!`) - #141663 (rustdoc: add ways of collapsing all impl blocks) - #143272 (Upgrade the `fortanix-sgx-abi` dependency) - #143585 (`loop_match`: suggest extracting to a `const` item) - #143698 (Fix unused_parens false positive) - #143859 (Guarantee 8 bytes of alignment in Thread::into_raw) - #144042 (Verify llvm-needs-components are not empty and match the --target value) - #144160 (tests: debuginfo: Work around or disable broken tests on powerpc) - #144431 (Disable has_reliable_f128_math on musl targets) r? `@ghost` `@rustbot` modify labels: rollup
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Rollup of 9 pull requests Successful merges: - #140871 (Don't lint against named labels in `naked_asm!`) - #141663 (rustdoc: add ways of collapsing all impl blocks) - #143272 (Upgrade the `fortanix-sgx-abi` dependency) - #143585 (`loop_match`: suggest extracting to a `const` item) - #143698 (Fix unused_parens false positive) - #143859 (Guarantee 8 bytes of alignment in Thread::into_raw) - #144160 (tests: debuginfo: Work around or disable broken tests on powerpc) - #144412 (Small cleanup: Use LocalKey<Cell> methods more) - #144431 (Disable has_reliable_f128_math on musl targets) r? `@ghost` `@rustbot` modify labels: rollup
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Rollup merge of #143859 - orlp:thread-into-raw-align, r=jhpratt Guarantee 8 bytes of alignment in Thread::into_raw When using `AtomicPtr` for synchronization it's incredibly useful when you've got a couple bits you can stuff metadata in. By guaranteeing that `Thread`'s `Inner` struct is aligned to 8 bytes everyone can use the bottom 3 bits to signal other things, such as a critical section, etc. This guarantee is thus very useful and costs us nothing.
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Guarantee 8 bytes of alignment in Thread::into_raw When using `AtomicPtr` for synchronization it's incredibly useful when you've got a couple bits you can stuff metadata in. By guaranteeing that `Thread`'s `Inner` struct is aligned to 8 bytes everyone can use the bottom 3 bits to signal other things, such as a critical section, etc. This guarantee is thus very useful and costs us nothing.
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Rollup of 9 pull requests Successful merges: - rust-lang#140871 (Don't lint against named labels in `naked_asm!`) - rust-lang#141663 (rustdoc: add ways of collapsing all impl blocks) - rust-lang#143272 (Upgrade the `fortanix-sgx-abi` dependency) - rust-lang#143585 (`loop_match`: suggest extracting to a `const` item) - rust-lang#143698 (Fix unused_parens false positive) - rust-lang#143859 (Guarantee 8 bytes of alignment in Thread::into_raw) - rust-lang#144160 (tests: debuginfo: Work around or disable broken tests on powerpc) - rust-lang#144412 (Small cleanup: Use LocalKey<Cell> methods more) - rust-lang#144431 (Disable has_reliable_f128_math on musl targets) r? `@ghost` `@rustbot` modify labels: rollup
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Pkgsrc changes: * Adjust patches to adapt to upstream changes and new versions. * assosicated checksums Upstream changes relative to 1.89.0: Version 1.90 (2025-09-18) ========================== Language -------- - [Split up the `unknown_or_malformed_diagnostic_attributes` lint] (rust-lang/rust#140717). This lint has been split up into four finer-grained lints, with `unknown_or_malformed_diagnostic_attributes` now being the lint group that contains these lints: 1. `unknown_diagnostic_attributes`: unknown to the current compiler 2. `misplaced_diagnostic_attributes`: placed on the wrong item 3. `malformed_diagnostic_attributes`: malformed attribute syntax or options 4. `malformed_diagnostic_format_literals`: malformed format string literal - [Allow constants whose final value has references to mutable/external memory, but reject such constants as patterns] (rust-lang/rust#140942) - [Allow volatile access to non-Rust memory, including address 0] (rust-lang/rust#141260) Compiler -------- - [Use `lld` by default on `x86_64-unknown-linux-gnu`] (rust-lang/rust#140525). - [Tier 3 `musl` targets now link dynamically by default] (rust-lang/rust#144410). Affected targets: - `mips64-unknown-linux-muslabi64` - `powerpc64-unknown-linux-musl` - `powerpc-unknown-linux-musl` - `powerpc-unknown-linux-muslspe` - `riscv32gc-unknown-linux-musl` - `s390x-unknown-linux-musl` - `thumbv7neon-unknown-linux-musleabihf` Platform Support ---------------- - [Demote `x86_64-apple-darwin` to Tier 2 with host tools] (rust-lang/rust#145252) Refer to Rust's [platform support page][platform-support-doc] for more information on Rust's tiered platform support. [platform-support-doc]: https://doc.rust-lang.org/rustc/platform-support.html Libraries --------- - [Stabilize `u*::{checked,overflowing,saturating,wrapping}_sub_signed`] (rust-lang/rust#126043) - [Allow comparisons between `CStr`, `CString`, and `Cow<CStr>`] (rust-lang/rust#137268) - [Remove some unsized tuple impls since unsized tuples can't be constructed] (rust-lang/rust#138340) - [Set `MSG_NOSIGNAL` for `UnixStream`] (rust-lang/rust#140005) - [`proc_macro::Ident::new` now supports `$crate`.] (rust-lang/rust#141996) - [Guarantee the pointer returned from `Thread::into_raw` has at least 8 bytes of alignment] (rust-lang/rust#143859) Stabilized APIs --------------- - [`u{n}::checked_sub_signed`] (https://doc.rust-lang.org/stable/std/primitive.usize.html#method.checked_sub_signed) - [`u{n}::overflowing_sub_signed`] (https://doc.rust-lang.org/stable/std/primitive.usize.html#method.overflowing_sub_signed) - [`u{n}::saturating_sub_signed`] (https://doc.rust-lang.org/stable/std/primitive.usize.html#method.saturating_sub_signed) - [`u{n}::wrapping_sub_signed`] (https://doc.rust-lang.org/stable/std/primitive.usize.html#method.wrapping_sub_signed) - [`impl Copy for IntErrorKind`] (https://doc.rust-lang.org/stable/std/num/enum.IntErrorKind.html#impl-Copy-for-IntErrorKind) - [`impl Hash for IntErrorKind`] (https://doc.rust-lang.org/stable/std/num/enum.IntErrorKind.html#impl-Hash-for-IntErrorKind) - [`impl PartialEq<&CStr> for CStr`] (https://doc.rust-lang.org/stable/std/ffi/struct.CStr.html#impl-PartialEq%3C%26CStr%3E-for-CStr) - [`impl PartialEq<CString> for CStr`] (https://doc.rust-lang.org/stable/std/ffi/struct.CStr.html#impl-PartialEq%3CCString%3E-for-CStr) - [`impl PartialEq<Cow<CStr>> for CStr`] (https://doc.rust-lang.org/stable/std/ffi/struct.CStr.html#impl-PartialEq%3CCow%3C'_,+CStr%3E%3E-for-CStr) - [`impl PartialEq<&CStr> for CString`] (https://doc.rust-lang.org/stable/std/ffi/struct.CString.html#impl-PartialEq%3C%26CStr%3E-for-CString) - [`impl PartialEq<CStr> for CString`] (https://doc.rust-lang.org/stable/std/ffi/struct.CString.html#impl-PartialEq%3CCStr%3E-for-CString) - [`impl PartialEq<Cow<CStr>> for CString`] (https://doc.rust-lang.org/stable/std/ffi/struct.CString.html#impl-PartialEq%3CCow%3C'_,+CStr%3E%3E-for-CString) - [`impl PartialEq<&CStr> for Cow<CStr>`] (https://doc.rust-lang.org/stable/std/borrow/enum.Cow.html#impl-PartialEq%3C%26CStr%3E-for-Cow%3C'_,+CStr%3E) - [`impl PartialEq<CStr> for Cow<CStr>`] (https://doc.rust-lang.org/stable/std/borrow/enum.Cow.html#impl-PartialEq%3CCStr%3E-for-Cow%3C'_,+CStr%3E) - [`impl PartialEq<CString> for Cow<CStr>`] (https://doc.rust-lang.org/stable/std/borrow/enum.Cow.html#impl-PartialEq%3CCString%3E-for-Cow%3C'_,+CStr%3E) These previously stable APIs are now stable in const contexts: - [`<[T]>::reverse`] (https://doc.rust-lang.org/stable/std/primitive.slice.html#method.reverse) - [`f32::floor`] (https://doc.rust-lang.org/stable/std/primitive.f32.html#method.floor) - [`f32::ceil`] (https://doc.rust-lang.org/stable/std/primitive.f32.html#method.ceil) - [`f32::trunc`] (https://doc.rust-lang.org/stable/std/primitive.f32.html#method.trunc) - [`f32::fract`] (https://doc.rust-lang.org/stable/std/primitive.f32.html#method.fract) - [`f32::round`] (https://doc.rust-lang.org/stable/std/primitive.f32.html#method.round) - [`f32::round_ties_even`] (https://doc.rust-lang.org/stable/std/primitive.f32.html#method.round_ties_even) - [`f64::floor`] (https://doc.rust-lang.org/stable/std/primitive.f64.html#method.floor) - [`f64::ceil`] (https://doc.rust-lang.org/stable/std/primitive.f64.html#method.ceil) - [`f64::trunc`] (https://doc.rust-lang.org/stable/std/primitive.f64.html#method.trunc) - [`f64::fract`] (https://doc.rust-lang.org/stable/std/primitive.f64.html#method.fract) - [`f64::round`] (https://doc.rust-lang.org/stable/std/primitive.f64.html#method.round) - [`f64::round_ties_even`] (https://doc.rust-lang.org/stable/std/primitive.f64.html#method.round_ties_even) Cargo ----- - [Add `http.proxy-cainfo` config for proxy certs] (rust-lang/cargo#15374) - [Use `gix` for `cargo package`] (rust-lang/cargo#15534) - [feat(publish): Stabilize multi-package publishing] (rust-lang/cargo#15636) Rustdoc ----- - [Add ways to collapse all impl blocks] (rust-lang/rust#141663). Previously the "Summary" button and "-" keyboard shortcut would never collapse `impl` blocks, now they do when shift is held - [Display unsafe attributes with `unsafe()` wrappers] (rust-lang/rust#143662) Compatibility Notes ------------------- - [Use `lld` by default on `x86_64-unknown-linux-gnu`] (rust-lang/rust#140525). See also <https://blog.rust-lang.org/2025/09/01/rust-lld-on-1.90.0-stable/>. - [Make `core::iter::Fuse`'s `Default` impl construct `I::default()` internally as promised in the docs instead of always being empty] (rust-lang/rust#140985) - [Set `MSG_NOSIGNAL` for `UnixStream`] (rust-lang/rust#140005) This may change program behavior but results in the same behavior as other primitives (e.g., stdout, network sockets). Programs relying on signals to terminate them should update handling of sockets to handle errors on write by exiting. - [On Unix `std::env::home_dir` will use the fallback if the `HOME` environment variable is empty] (rust-lang/rust#141840) - We now [reject unsupported `extern "{abi}"`s consistently in all positions] (rust-lang/rust#142134). This primarily affects the use of implementing traits on an `extern "{abi}"` function pointer, like `extern "stdcall" fn()`, on a platform that doesn't support that, like aarch64-unknown-linux-gnu. Direct usage of these unsupported ABI strings by declaring or defining functions was already rejected, so this is only a change for consistency. - [const-eval: error when initializing a static writes to that static] (rust-lang/rust#143084) - [Check that the `proc_macro_derive` macro has correct arguments when applied to the crate root] (rust-lang/rust#143607)
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When using
AtomicPtrfor synchronization it's incredibly useful when you've got a couple bits you can stuff metadata in. By guaranteeing thatThread'sInnerstruct is aligned to 8 bytes everyone can use the bottom 3 bits to signal other things, such as a critical section, etc.This guarantee is thus very useful and costs us nothing.